Automotive vehicles can be involved in crash accident. In particular side crash can cause the handle to move inadvertently to unlatched position. Doors are unlatched and swung open, thus occupants are exposed to greater risk of being expelled from the vehicles. Many mandatory side crash tests are set up for vehicles. One requirement of these tests is that the vehicle doors remain closed during and after side crash test, in which the vehicle is hit from side. To measure side crash severity, acceleration in terms of G, (1 G=9.8 m/sec^2) is used. Very often, side crash is very severe that acceleration can be as high as 200 G in a very short of time interval. In side crash test, the acceleration is a spatial vector with lateral component parallel to the side impact, and vertical component perpendicular to the side impact. It is also a random time sequence, varies with the time.
Typically, a safety device against inadvertent move of the handle uses a counterweight mounted in the exterior handle assembly to reduce or to stop the handle move during side crash, because the counterweight's move under the inertia force makes the handle to move against the inertia force on the handle. One of the widely used design is to integrate counter weight into bell crank lever with a certain offset to the lever's pivot, such that the inertia force on the counter weight make the bell crank lever move against the handle's move under the inertia force. The bell crank lever transfers the handle's move and unlatches the latch. Or the counter weight can be a separate component, as described in the U.S. Pat. No. 7,070,216 B2. However, when the acceleration of the side crash is very high, e.g. 200 G, counterweight of suitable size fit into current automotive doors can not stop the handle from inadvertent move. Further when counterweight, which is integrated into the bell crank lever, is made large and heavy as required, it can easily overcome the spring bias and rotate to unlatch the latch under the vertical component of the inertia force, even that the exterior handle is not activated by the lateral component of the inertia force.
Additional components can be added to the door handle assembly as safety device, in which a component blocks the unlatching movement between the handle and the latch due to the inertia force, like the one mentioned in the U.S. Pat. No. 7,201,405 B2. However, it is highly possible and often the case that the handle already moves out passing a threshold and cause the latch to unlatch the door before this particular component begin to move as to block the handle's inadvertent movement. This is because that blocking component(s) and the handle have different dynamic behavior due to the acceleration nature of the side crash. Side crash has inertia force of spatial vector in orientation and random time sequence in magnitude. It is quite common that by the time a blocking component come into the engagement to block the unlatching movement, the component to be blocked/stopped has already gained some speed. The sudden block/stop induces very high stress on the blocking component and the one to be blocked, such that fatigue develops over the time. Eventually one or both of the components break.